std::tolower

From Cppreference

C++ Standard Library
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Strings library
Narrow character strings Wide character strings Classes basic_string char_traits
Narrow null-terminated strings
Functions Character manipulation isalnum isalpha islower isupper isdigit isxdigit iscntrl isgraph isspace isprint ispunct tolower toupper Conversions to numeric formats atof atoi strtol strtoul strtof String manipulation strcpy strncpy strcat strncat strxfrm String examination strlen strcmp strncmp strcoll strchr strrchr strspn strcspn strpbrk strstr strtok Memory manipulation memchr memcmp memset memcpy memmove Miscellaneous strerror

Defined in header <cctype>
int tolower( int ch );

Converts the given character to lowercase.

[edit] Parameters

ch

-

character to be converted

[edit] Return value

converted character or ch if no such conversion was possible

[edit] See also

toupper	converts a character to uppercase (function)